Abstract

Background: Traffic noise is interfering during day- and nighttime causing distress and adverse physiological
reactions in large parts of the population. Railway noise proved less annoying than aircraft noise in surveys
which were the bases for a so called 5 dB railway bonus regarding noise protection in many European countries.
Objectives: The present field study investigated railway noise-induced awakenings during sleep, nighttime
annoyance and the impact on performance the following day. Comparing these results with those from a
field study on aircraft noise allowed for a ranking of traffic modes concerning physiological and psychological
reactions.
Methods: 33 participants (mean age 36.2 years±10.3 (SD); 22 females) living alongside railway tracks around
Cologne/Bonn (Germany) were polysomnographically investigated. These data were pooled with data from a
field study on aircraft noise (61 subjects) directly comparing the effects of railway and aircraft noise in one
random subject effects logistic regression model. Annoyance was rated in the morning evaluating the previous
night.
Results: Probability of sleep stage changes to wake/S1 from railway noise increased significantly from 6.5% at
35 dB(A) to 20.5% at 80 dB(A) LAFmax. Rise time of noise events had a significant impact on awakening probability.
Nocturnal railway noise led to significantly higher awakening probabilities than aircraft noise, partly
explained by the different rise times, whereas the order was inversed for annoyance. Freight train noise compared
to passenger train noise proved to have the most impact on awakening probability. Nocturnal railway
noise had no effect on psychomotor vigilance.
Conclusions: Nocturnal freight train noise exposure in Germany was associated with increased awakening probabilities
exceeding those for aircraft noise and contrasting the findings of many annoyance surveys and annoyance
ratings of our study. During nighttime a bonus for railway noise seems not appropriate